According to the known art, the film thickness varies from a minimum of microns to a maximum of 70 microns. The film dissolving time clearly increases on increasing the thickness. The ideal, to achieve a dissolving time of a few seconds, is to maintain the thickness around 35÷45 microns. To be of practical applicability, the surface of a film usable for cosmetic, food or pharmaceutical purposes must have an area of about 6/8 cm2 and a weight variable between 25 and 35 milligrams.